{"id":"CVE-2026-109753","title":"Incorrect boundary conditions in the Layout component","summary":"Incorrect boundary conditions in the Layout component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","cwe":["CWE-119"],"vendor":"Mozilla","product":"Firefox","affected":["Firefox","Thunderbird"],"published":"2026-10-13","updated":"2026-10-15","sourceUpdated":"2026-10-15T20:17:07.910","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-109753","references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2068441","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-107/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-108/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-109/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-110/","label":"security@mozilla.org"}],"tags":["nvd","cve.org"],"epss":0.00343,"epssPercentile":0.27622,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-15T19:19:11.897065Z"},"ingestedAt":"2026-10-13T13:27:04.008Z","slug":"CVE-2026-109753","body":"## Overview\n\nIncorrect boundary conditions in the Layout component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":222743,"id":"CVE-2026-109753","ts":1792097075886,"field":"cvss","old":null,"new":"8.1"},{"seq":222742,"id":"CVE-2026-109753","ts":1792097075886,"field":"severity","old":"none","new":"high"}]}